NEWTOWN, Conn. — As this small town mourned the victims of one of the nation's worst school shootings, state police said Sunday that the gunman carried multiple 30-round magazines of ammunition and hundreds of bullets when he launched his bloody rampage that killed 26 people.

Connecticut State Police Lt. Paul Vance said authorities had publicly identified the gunman as Adam Lanza, 20. His mother Nancy was one of the victims of Friday's shootings.

Vance, delivering a brief report on the investigation into the slayings, said Lanza used a .223 Bushmaster asssault rifle for most of the killings and also had two handguns, a Glock 10 mm and a Sig Sauer 9 mm. Vance said he used the assault rifle on his school victims before killing himself with a handgun.

The Bushmaster is a type of gun commonly seen at competitions and was the type used in the 2002 sniper killings in the Washington area. Vance said the assault rifle magazines each contained 30 rounds.

In addition to the fusillade of shell casings recovered at the scene, Vance said hundreds more unexpended rounds were found at the scene with the dead shooter. A fourth weapon, a shotgun, was found in the car Lanza drove to the school.

Vance said investigators are trying to determine a motive. "this is a very long, tedious process,'' he said of the investigation. "It's going to take many, many man hours to attempt to ... put this puzzle together.''

President Obama was arriving here to speak at an evening memorial service.

Also Sunday, President Obama was schedule to arrive and speak at an evening memorial service.

In Washington, Sen. Joe Lieberman, I-Conn., and Sen. Dick Durbin, D-Ill., told Fox News Sunday that a national commission could scrutinize gun laws, the mental health system and the impact that violent video games might have in gun violence. Sen . Dianne Feinstein, D-Calif., promised to introduce a ban when Congress returns in January.

"It can be done," Feinstein told NBC's Meet the Press.

The drive for stiffer gun laws came as law enforcement officials here continued the painful business of investigating details of Friday's senseless slaughter that left dead a deranged gunman and his 27 victims.

Connecticut's chief medical examiner, H. Wayne Carver II, said Sunday that Adam Lanza, 20, shot his mother, Nancy, multiple times in the head before going to Sandy Hook Elementary school and gunning down 26 people, including 20 children. Carver said Lanza then killed himself with a gunshot wound to the head.

At an earlier briefing, Connecticut State Police Lt. Paul Vance said "misinformation" was being posted on some social websites, some of it "in a threatening manner" by people posing as the shooter, law enforcement officials and others close to the investigation.

"These issues are crimes, they will be investigated, state and federally, and prosecution will take place" when those posting the information are identified," Vance said.

Vance reiterated that authorities have recovered some evidence he believes will help explain what prompted Adam Lanza to launch his killing spree. Vance declined to elaborate on the nature of the evidence. But he said local and federal investigators were tracing the weapons used in the attack, including the .223-caliber assault rifle used in the killings, "all the way back to the work bench'' to learn how they ended up in Lanza's possession.

Three weapons found at the scene, two handguns and the rifle, were registered to Lanza's mother, who was killed before Lanza set out for the school.

"A great deal of work must be done on those weapons,'' Vance said.

Federal law enforcement officials are visiting area gun dealers and shooting ranges that could provide additional information about the gunman's preparations before Friday's attacks. Authorities have cast a broad investigative net with a goal of interviewing an estimated 400 dealers and range operators in a four-county area.

Dean Price, manager of the Wooster Mountain Shooting Range, about 15 miles from the school, said two agents from the Bureau of Alcohol, Tobacco, Firearms and Explosives spent about two hours going through all the sign-in sheets for 2012. Price said the agents were trying to determine if either Nancy or Adam Lanza had been at the range. Neither had, Price said, adding that he did not know either of them.

On Saturday, the horrifying details about the victims' last moments emerged as authorities released their names and ages — the youngest 6 and 7, the oldest 56. Many of the Sandy Hook Elementary victims were shot several times at close range by an assault rifle,Carver said.

Ana Marquez-Greene, 6, and her family moved to Connecticut just two months ago, drawn from Canada, in
part, by Sandy Hook's pristine reputation, said her grandmother, Elba Marquez. The grandmother's brother, Jorge
Marquez, is mayor of a Puerto Rican town and said the child's 9-year-old
brother was also at the school but escaped safely. Twitter

"All of the wounds I know of were caused by a rifle,'' he said. Twelve of the youngsters killed were girls, eight were boys. All six school officials, including principal Dawn Hochsprung, were women. Sixteen of the kids were just 6 years old; the rest were seven.

"I've been at this for a third of a century,'' Carver said of the gruesome crime scene and young victims, who were massacred in one of the worst mass shooting sprees in U.S. history. "This is probably the worst I've seen or the worst any of my colleagues have seen. This was a very devastating set of injuries."

All the victims of the Connecticut elementary school shooting were killed up close by multiple rifle shots, a medical examiner said.

Ray Horvath walked out the front doors of Sandy Hook school Friday morning — minutes before Adam Lanza forced his way in.

"I wish the hell I was there," said the retired 65-year-old Newtown resident, who runs a non-profit group that administers a before-and-after school program for children. "I would rather have given up my life for another."

Horvath says he left the school that day and drove to a local hardware store nearby, where he watched unmarked police cars speeding to the school. Four 6-year-olds in Horvath's program — Ben Wheeler, Noah Pozner, Jesse Lewis and James Matiolli — were murdered.

"They all had bright-eyed wonder and curiosities," says Horvath. "James was a sweetheart of a kid with such an innocent face."

Horvath says he talked every day with the school's principal, Dawn Hochsprung, who was also slain.

"She always had a smile on her face and was a wonderful woman," Horvath says. "I'll never forget the special day she dressed for the kids as a princess with a wand. She had sparkles on her eyelashes, so, when she blinked, her eyes sparkled."President Obama plans to travel to Newtown tonight to meet with victims' families and thank first-responders. He will speak at an interfaith vigil at Newtown High School.

Family members, friends and former classmates say Adam Lanza was bright, extremely shy, socially awkward and may have suffered from Asperger Syndrome, a form of autism.

The killer's family was struggling to make sense of what happened and "trying to find whatever answers we can," his father, Peter Lanza, said in a statement late Saturday that expressed sympathy for the victims' families. Peter and Nancy Lanza were divorced.

Investigators tried to figure out what led a bright but painfully awkward 20-year-old to slaughter 26 children and adults at a Connecticut elementary school. (Dec. 15)

Vance said family members have asked the news media to respect their privacy. "This is an extremely heartbreaking thing for them to endure," he said. State troopers have been assigned to stand outside the homes of victims' families to protect their privacy, he said. A crisis intervention team from Yale University has been set up for people in town who may need to talk to someone, Vance said.

At church vigils and gatherings around Newtown, there was a collective cry of disbelief and grieving. Around town, flags flew at half staff. On Church Hill Road, which leads into Sandy Hook, a large sheet hung on the side of a bridge. The blue lettering read "We (heart) you Sandy Hook Elementary."

As the names of the 26 children and adults who were gunned down at an elementary school in Newtown, Conn,. were made public on Saturday, the shock of Friday's massacre gave way to a profound grief. (Dec. 15)

"We are in the process of meeting with families," said funeral director Daniel Honan.

A candlelight prayer service was held Saturday night in front of Edmond Town Hall in Newtown, Conn.(Photo: Robert Deutsch, USA TODAY)

Separately, members of the Connecticut Funeral Directors Association were meeting to determine how they can help Honan and families of victims, said the association's spokeswoman, Laura Soll.

Declan Procaccini was with his daughter at Sandy Hook Elementary in a reading class with other children and two teachers on Friday when the shooting started. He said they locked themselves in a bathroom until police banged on the door and led then through the school and the bloody scene to safety.

Laura and Nick Phelps have a 6-year-old boy who is a first-grader and a daughter in third grade. Both got out safely. Laura Phelps told CNN her son "said he saw people on the floor, sleeping." They said their son doesn't seem to understand what happened. Their daughter is more upset.

"They all heard and saw things children shouldn't see," she said. "It's unspeakable. It's like reaching into your insides and pulling them out. ... It's something we'll get through, but I don't think it's something we'll ever get over."

The father of a 6-year-old girl killed in the Connecticut elementary school massacre says his deep pain is comforted by the memory of how bright, loving and creative his daughter was. (Dec. 15)

After receiving word of the shooting, Tracy Hoekenga said she was paralyzed with fear for her two boys, fourth-grader C.J. and second-grader Matthew. "I couldn't breathe. It's indescribable. For a half an hour, 45 minutes, I had no idea if my kids were OK," she said.

The nightmare on Friday began when Adam Lanza drove his mother's car through 300-year-old Newtown to he village of Sandy Hook, where teacher Theodore Varga and other fourth-grade instructors were meeting; the glow remaining from a fourth-grade concert Thursday night.

"It was a lovely day," Varga said. "Everybody was joyful and cheerful. We were ending the week on a high note."

The incident is the latest in a series of mass shootings in the U.S. this year, including Tuesday's assault by a lone gunman at a Portland, Ore., shopping mall that left two dead and one wounded.

The family of Nancy Lanza, the mother of elementary school shooter Adam Lanza, issued a statement of grief and condolence about Friday's massacre through local law enforcement in Kingston, N.H. (Dec. 15)

People pause for a moment of silence for 26 shooting victims at a makeshift memorial on Dec. 21 in Newtown, Conn. Church bells rang at 9:30 a.m. across the nation to mark the one-week anniversary of the Sandy Hook Elementary School massacre. John Moore, Getty Images

Virginia Gov. Bob McDonnell, left, talks with Gabriel Smith after a ceremony of remembrance for the victims of the Connecticut school shooting at the Bell Tower in Capitol Square in Richmond, Va. Bob Brown, Richmond Times-Dispatch, via AP

Boy Scouts salute as the funeral procession for Benjamin Wheeler, 6, enters Trinity Episcopal Church on Dec. 20 in Newtown, Conn. Benjamin, a member of Tiger Scout Den 6, was killed when a gunman opened fire inside Sandy Hook Elementary School on Dec. 14. John Moore, Getty Images

The casket of teacher Anne Marie Murphy is carried from St. Mary Of The Assumption Church after her funeral service in Katonah, N.Y. Murphy was killed on Dec. 14 when a gunman opened fire in Sandy Hook Elementary School in Newtown, Conn. Craig Ruttle, AP

A child lines up with firefighters during the funeral for school shooting victim Daniel Barden at St. Rose of Lima Catholic Church in Newtown, Conn. The 7-year-old, who was one of 26 people killed Dec. 14 at Sandy Hook Elementary School, dreamed of being a firefighter one day. Charles Krupa, AP

People carry Victoria Soto's casket from Lordship Community Church in Stratford, Conn. Soto reportedly died while trying to protect her students during the shooting rampage Dec. 14 at the school in Newtown. Brendan Smialowski, AFP/Getty Images

Glenn Mackbach lights a candle at a memorial honoring the Sandy Hook Elementary School shooting victims on Dec. 18 in Newtown, Conn. Mackbach and his friends visit the memorial when they get out of school and work to relight candles. David Goldman, AP

Cindy Mattioli hugs her daughter Anna at the funeral of her son James at the St. Rose of Lima Catholic Church in Newtown Conn., on Dec. 18. James was a first grader and victim of the Dec. 14 massacre. Robert Deutsch, USA TODAY

Police are positioned outside the home of Nancy Lanza on Dec. 18 in Newtown, Conn. Nancy Lanza was killed by her son Adam before going on his rampage at Sandy Hook Elementary School on Dec. 14. Don Emmert, AFP/Getty Images

Saba Quraishi holds a Tibetan bowl that she was ringing across the street from the Honan Funeral Home in Newtown, Conn., as the funeral procession for Jack Pinto made its way to the cemetery. Eileen Blass, USA TODAY

Linda Hoyt of Danbury, Conn., right; her son Jeffrey, 16, middle; daughter Kristin, 18; and Linda's niece, Chelsea Crain, 23, tie balloons on a bridge over Interstate 84 on Dec. 16, one day after a gunman opened fire at nearby Sandy Hook Elementary School, killing 20 children and six adults. They put up 20 white and gold balloons, one for each child, and six blue balloons for the adults who died on Dec. 14. Linda Hoyt said: "I'm so sad for all the children and all the families. God's beautiful children. It's so sad." Eileen Blass, USA TODAY

Audrey Petschek of Sandy Hook, Conn., takes a picture of a flag covered with numbers representing the people that died when a gunman opened fired at Sandy Hook Elementary School. Eileen Blass, USA TODAY

Gary Seri, general manager at the Stone River Grille, hangs a message written on a tablecloth in honor of the teachers who died along with students a day earlier when a gunman opened fire at Sandy Hook elementary school in Newtown, Conn. Seri, who put up red balloons that were not used when a sweet 16 party was canceled the night before in light of the massacre, said the teachers were scheduled to have their holiday party at his restaurant. Julio Cortez, AP

A prayer vigil was held at the Newtown United Methodist Church Friday evening in honor of people killed earlier in the day, including 20 schoolchildren at the Sandy Hook elementary school. Robert Deutsch, USA TODAY

Parents leave a staging area after being reunited with their children following a shooting at Sandy Hook Elementary School in Newtown, Conn., about 60 miles northeast of New York City, on Dec. 14. Jessica Hill, AP

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Police said the shootings took place in two rooms in one section of the school building, including a kindergarten classroom.

As the shooting erupted, quick-thinking teachers and faculty members hid some students in closets and bathrooms, while others rounded up students and spirited them out of the building.

"A lot of children are alive today because of actions the teacher took," Dr. Janet Robinson, superintendent of the Newtown Public School District, told CNN. Robinson said Hochspring died trying to block Lanza.

Vance said the murder scene was so gruesome that first responders, including tactical squad police, were provided counseling later in the day. "This was a tragic, horrific scene they encountered,'' he said.

Sandy Hook is in a residential, wooded village in the town of Newtown about 65 miles northeast of New York City. The school, which serves kindergartners to fourth-graders, has 39 teachers and nearly 700 students. A reverse 911 call went out to parents warning of an incident, shaking the quiet, middle- and upper-middle class community of 27,000 to its core.

"This is the most tragic thing we've ever encountered,'' said Newtown Police Lt. George Sinko. "We have to think about the families right now."

A gunman killed 20 students and six adults at Sandy Hook Elementary School in Newtown, Conn., on Friday morning. Police said the shootings took place in two rooms at the school. At least three weapons were recovered at the scene, including an assault rifle and two semiautomatic handguns. Here is what is known.